Measuring tape devices which have a measuring tape coiled within a casing having an aperture through which the tape can be extracted and retracted have been known for years. In many such measuring tape devices, the coilable tape is spring-loaded to be biased toward a retracted condition. Some devices have various types of brake or locking mechanisms operatively associated with the tape to hold the tape in any given extended position. The locking mechanisms usually operate on the tape within the casing, and an actuator, such as a slide or push button, is exposed exteriorly of the casing. Upon actuating the slide or push button, the tape is locked in a given extended position, and upon releasing the slide or push button the tape is retracted automatically into the casing under the influence of its spring loading.
Other such measuring tape devices have a brake mechanism which, in normal condition, applies a limited brake or a drag on the tape. Again, operative components of the brake mechanism are disposed within the casing, and an actuator is exposed exteriorly of the casing for actuation by a user. During use, the tape is extracted from the casing against a predetermined load or drag applied by the brake mechanism. For instance, the drag may be determined by an internal spring. Upon movement of the actuator, the drag is released and the tape retracts automatically into the casing under the influence of its spring loading.
Heretofore, whenever a measuring tape device has incorporated a brake mechanism, it generally has been one or the other of the two forms described above. In other words, either the device had a positive brake which applied a considerable load on the tape to positively lock the tape in a given position of extension which does not enable the user to readily extract the tape in a controlled fashion, or the device had a brake mechanism which applied a lesser drag on the tape for controlled manipulation but the drag was insufficient to positively lock the tape once a precise measurement is made. These limitations on the different types of brake mechanisms have inhibited their use by skilled craftsmen.
Skilled craftsmen such as carpenters, wall paper hangers, tile layers, electricians, plumbers and the like use a coilable measuring tape device in a wide range of circumstances wherein both a positive brake and a controlled drag would be highly advantageous but heretofore has not been available.
For instance, tile layers most often use a measuring tape device which has a brake mechanism for applying a controlled drag on the tape whereby very precise measurements can be made. The device actually becomes a form of template (i.e. length) and may even be extended over a surface to which adhesive has been applied. In using a device which only has a brake mechanism with a controlled drag to obtain a precise measurement, the controlled drag is too easily overcome by accident in moving from one area of a floor to another area and the precise measurement or template length is lost, whereupon the measurement has to be retaken or, if not discovered, misalignment of the tile will occur. On the other hand, if a measuring tape device having only a brake mechanism which applies a strong positive lock on the tape is used, precise measurements are difficult to obtain because the tape is constantly being biased toward its retracted condition under the influence of its spring loading. Usually, the craftsman has to use two hands or the tape may get out of control and wipe over the adhesive, resulting in lost time if not destruction of the device itself because of adhesive getting into the internal mechanisms.
Carpenters use measuring tape devices in many applications which are not common to an ordinary user. In just one example, a carpenter may be measuring downward from an elevated position. Such a craftsman, contrary to an ordinary layman, using a measuring tape device with a brake mechanism having a controlled drag, will grasp the distal end of the tape itself and shake the device whereupon the casing, through its own weight, will descend to a lower position. The craftsman then will latch the casing itself under some structure from which a measurement is to be made, check the "top" or distal end of the tape, and then lift the casing to read and thereby calculate his precise measurement for repeating that measurement downline of the structure, having to go to considerable effort to insure that the measurement is not lost. This would be impossible with a device which incorporates a brake mechanism having only a positive brake. If that same device with its controlled drag mechanism also had a positive brake mechanism, the carpenter could set the device to the precise measurement and repeat the measurement downline of the structure without concern that the measurement will be lost in the process. Heretofore, this could not be done.
Still another example of the problems with available measuring tape devices can be exemplified with a craftsman who hangs wallpaper and, again, often uses a measuring tape device as a tool for purposes beyond mere measuring lengths. This craftsman, of course, often uses a measuring tape device for measuring the length of strips of wallpaper. A device with a brake mechanism having only a positive lock might be used because it can be set to consistently measure repeated lengths of wallpaper with minimal chance of accidentally losing the measurement. However, an experienced craftsman more likely would use a device with a brake device having a given drag because he also uses the tape itself to establish plumb lines as he hangs the paper. In other words, the skilled craftsman again would grasp the distal end of the tape itself at the top of a wall and allow the tape to hang by gravity under the weight of the casing. If the casing does not reach all the way to the bottom of the wall, he might shake the tape in a vertical direction so that the casing will bounce and "extract" relative to the tape against the drag until the tape is extended from the casing a sufficient distance This procedure could not be performed with a device having only a brake mechanism with a positive drag, yet, again, the craftsman runs the risk of losing his measurement without a positive lock. It can be seen that this dilemma continues in all kinds of fields of expertise and examples can be given practically "ad infinitum".
This invention is directed to providing a measuring tape device of the character described which solves the above and many other problems in a wide variety of trades and to satisfy the need for a novel measuring tape device having a dual brake or lock system.